In this study, we experimentally investigate fluid–fluid displacement in a Hele–Shaw cell where the two fluids react, upon mixing, to form solid precipitates. Under the conditions of our experiments, we observe that precipitation reaction along the moving fluid–fluid interface generates solids in the form of mineral particle suspensions. We show that the emergence, growth and decay of the fingering pattern are strongly influenced by the injection rate and the initial fluid chemical concentrations. In addition, we show that precipitation-induced fingering has a strong feedback on fluid–fluid mixing and the subsequent precipitation rate. Lastly, we find that, counter to intuition, a higher injection rate results in a larger amount of precipitates that are securely deposited in the Hele–Shaw cell.
This work is led by Negar Shahsavar (Zhao lab @ McMaster University), and is a collaborative effort with Dr. Benzhong (Robin) Zhao at McMaster.
Read the paper here.